Add a converter for dt.timedelta.

[mjohanse-emr]

What does this Pull Request accomplish?

• Adds a converter between datetime.timedelta and duration_pb2.Duration.
• Adds unit tests for this converter.
• Adds a datetime.timedelta value to the "all types" example.
  • Shows up as an indicator only. There wasn't a suitable control to use unless we input hours/minutes/seconds separately. I don't think it's a common use case to want to input a timedelta on the panel, so I think this is sufficient.

Why should this Pull Request be merged?

Implements part of AB#3164818

What testing has been done?

Unit tests, mypy, pyright, styleguide.

I ran the "all types" example and this is what shows up for dt_datetime:

[github-actions]

Test Results

   10 files  ± 0     10 suites  ±0   23s ⏱️ -8s
  227 tests + 3    227 ✅ + 3  0 💤 ±0  0 ❌ ±0 
2 220 runs  +30  2 220 ✅ +30  0 💤 ±0  0 ❌ ±0 

Results for commit 29ab5ea. ± Comparison against base commit 5ade5a6.

This pull request removes 26 and adds 29 tests. Note that renamed tests count towards both.

tests.unit.test_convert ‑ test___various_python_objects___get_best_matching_type___returns_correct_type_string[python_object11-Collection.bool]
tests.unit.test_convert ‑ test___various_python_objects___get_best_matching_type___returns_correct_type_string[python_object12-Collection.bytes]
tests.unit.test_convert ‑ test___various_python_objects___get_best_matching_type___returns_correct_type_string[python_object13-Collection.float]
tests.unit.test_convert ‑ test___various_python_objects___get_best_matching_type___returns_correct_type_string[python_object14-Collection.int]
tests.unit.test_convert ‑ test___various_python_objects___get_best_matching_type___returns_correct_type_string[python_object15-Collection.str]
tests.unit.test_convert ‑ test___various_python_objects___get_best_matching_type___returns_correct_type_string[python_object16-Collection.bool]
tests.unit.test_convert ‑ test___various_python_objects___get_best_matching_type___returns_correct_type_string[python_object17-Collection.bytes]
tests.unit.test_convert ‑ test___various_python_objects___get_best_matching_type___returns_correct_type_string[python_object18-Collection.float]
tests.unit.test_convert ‑ test___various_python_objects___get_best_matching_type___returns_correct_type_string[python_object19-Collection.int]
tests.unit.test_convert ‑ test___various_python_objects___get_best_matching_type___returns_correct_type_string[python_object20-Collection.str]
…

tests.unit.test_convert ‑ test___durationpb2_timestamp___from_any___valid_python_value
tests.unit.test_convert ‑ test___python_datetime_timedelta___to_any___valid_durationpb2_value
tests.unit.test_convert ‑ test___various_python_objects___get_best_matching_type___returns_correct_type_string[python_object11-timedelta]
tests.unit.test_convert ‑ test___various_python_objects___get_best_matching_type___returns_correct_type_string[python_object12-Collection.bool]
tests.unit.test_convert ‑ test___various_python_objects___get_best_matching_type___returns_correct_type_string[python_object13-Collection.bytes]
tests.unit.test_convert ‑ test___various_python_objects___get_best_matching_type___returns_correct_type_string[python_object14-Collection.float]
tests.unit.test_convert ‑ test___various_python_objects___get_best_matching_type___returns_correct_type_string[python_object15-Collection.int]
tests.unit.test_convert ‑ test___various_python_objects___get_best_matching_type___returns_correct_type_string[python_object16-Collection.str]
tests.unit.test_convert ‑ test___various_python_objects___get_best_matching_type___returns_correct_type_string[python_object17-Collection.bool]
tests.unit.test_convert ‑ test___various_python_objects___get_best_matching_type___returns_correct_type_string[python_object18-Collection.bytes]
…

♻️ This comment has been updated with latest results.